1. General
    1. What is REI3?
    2. I can just download REI3 and start using it? No licenses? No user limits?
    3. Can I build any application with REI3?
    4. Can anyone write applications with REI3?
    5. How is REI3 different from low-code application builders?
    6. Can I migrate data to or from REI3?
  2. Business
    1. Why should my organization use REI3?
    2. How are you making money with a free software?
    3. Can I get a discount for my organization?
    4. Can I charge money for my application?
    5. Are you supporting my self-built applications?
  3. Technical
    1. Can I run REI3 on my system?
    2. Can I install REI3 on my devices?
    3. How does REI3 handle mobile devices?
    4. Can I host REI3 in the cloud?
    5. Is it safe to download and install applications?


What is REI3?

REI3 is an open (free to use and open source) business application platform. Anyone can deploy applications or create new ones with REI3 to fulfill their software requirements. Application authors can choose to keep applications internal or publish them for others to use. Applications can also be built-on to extend them or to re-use existing data structures, user interfaces and so on.

I can just download REI3 and start using it? No licenses? No user limits?

Yes. REI3 is free to use for anyone. You can build your own applications or access the public repository from inside REI3´s admin panel to install published applications.

Developers of REI3 have joined Lean Softworks, a German software solution company, to offer professional services for organizations; these services are and will stay optional however.

Can I build any application with REI3?

No. Any software, including REI3, has strengths and weaknesses. For one, REI3 is built on web technologies. Many requirements can easily be met with a REI3 application; however, native applications continue to have benefits as they are running outside of a browser.

On the other side, REI3 is very strong when it comes to fulfilling internal software needs. It can handle records of all kinds, can easily work with dates and calendars, allows for file and mail processing, support workflows, limit data access where necessary and much more.

Can anyone write applications with REI3?

Mostly yes. All REI3 applications are written with the graphical application builder, or 'Builder' for short. The Builder helps application authors define their data structures, create user interfaces, limit access to certain records and so on.

However, REI3 cannot do the thinking for an author. It can make building applications easy, but deciding, which relationships are required on a data level or how business logic should function, is up to the author. Almost anyone can build simple applications. IT knowledge in general, and experience with relational databases in particular, allow for powerful, complex applications to be built.

How is REI3 different from low code application builders?

Every software has its focus - low code tools included. REI3´s focus is on allowing for simple applications to be built easily, while also enabling complex software requirements to be met. It is probably not as user-friendly as some tools out there, but gives direct access to functions that many low code tools abstract away for the sake of simplicity.

With REI3, authors can build simple applications in minutes. But they can also create custom indexes to tweak performance. Or create triggers on database tables to enforce compliance and to execute additional business logic. User interfaces can work with a single record, or join relations to update multiple records at the same time. When retrieving data, joins and complex filters are available - as are sub queries, nested if necessary. Relation access policies, backend & frontend functions, deferred triggers and much more is available and documented inside of REI3.

Can I migrate data to or from REI3?

Yes. There is support to copy data to/from REI3 via its integrated API. For most use cases, a CSV import/export function is most convenient however. Both are available to migrate data.


Why should my organization use REI3?

Because we can cheaply fulfill many different software requirements. Basic requirements, like time tracking or task management, can be met directly. Niche or complex requirements can easily be addressed by extending or building new applications with REI3.

While REI3 cannot do everything (no software can), in many cases REI3 can be used to replace multiple software providers to reduce license or maintenance costs. It can also serve as a professional replacement for Excel or Access based 'solutions'; allowing for authenticated, multi-user access with all the features of the REI3 platform, such as: notifications, change histories, access permissions, workflows, and so on.

How are you making money with a free software?

Organizations that rely on REI3 can choose to purchase service agreements or work with us to build and maintain applications. We finance ourselves by helping organizations cheaply address requirements or replace expensive software solutions.

Can I get a discount for my organization?

Maybe. Discounts are usually not a problem for very small organizations or those working in the educational space or for charitable purposes. Just contact us via our contact form with your request.

Can I charge money for my application?

Yes. When you build REI3 applications, you own them. By checking the application signature, your clients can verify the authenticity of the application and be sure of its origin.

We fully support and endorse companies building solutions on REI3 to offer to their clients. We do not take ownership of the product nor take any cut of agreed upon service agreements between application authors and their clients.

In the future, we might expand the official REI3 repository to allow easy access to and purchase of commercial REI3 applications. In this scenario, some servicing fees will likely be introduced. This however, would only be an optional service - not required for building, publishing or selling REI3 applications or services around them.

Are you supporting my self-built applications?

Yes, within reason. Without any service agreement, we will look at service requests and try to help where we can. However, paying clients will come first as we need to secure future operations and continuous development of the REI3 platform.

We are always happy to see what people build and how they address their specific requirements. While working with application authors without service agreements, we collect valuable experience and perspective - this however does not pay the bills so we need to balance it out.


Can I run REI3 on my system?

Most likely yes. You need a Windows or Linux server to install REI3 on. With REI3 running, any device with a modern browser can utilize REI3.

Can I install REI3 on my devices?

Kinda. REI3 is based on web technologies; after installing it on a server, any device with a browser can access it. However, REI3 supports PWA (progressive web app) standards and allows 'installation' on devices that support it. On iOS and Android, REI3 can be installed to the home screen, while on Windows Chrome supports installation as well.

How does REI3 handle mobile devices?

As good as you make it. REI3 fully supports mobile devices that come with a modern browser. REI3 applications work on smaller screens without any additional effort. However, by tuning user interfaces they can be made very user friendly on mobile devices.

Can I host REI3 in the cloud?

Yes. REI3 is built on web services; as long as you secure your public facing servers, your network and so on, there is no reason, not to run REI3 in the cloud. Just be aware that any software can be subject to yet unknown exploits and vulnerabilities. The more useful an application becomes, the more interesting it might be as a target for attack.

While we also run productive REI3 instances in the cloud, we keep critical data local, with access secured by modern VPN solutions.

Is it safe to download and install applications?

Applications offered in our official application repository are checked and signed by us (the REI3 developers). We make sure that they are safe to use.

When it comes to applications from third parties, it is up to you, who you trust with your system and data. When you want to install applications from other authors, you need to add their public key to your REI3 instance. This way your system can check their origin and authenticity. If anyone tries to alter or fake existing applications, their signature will not validate and REI3 will block the installation.

There is however no one stopping you from installing any public key; only accept public keys from trusted sources, like known service providers.